Coregulatory Networks Remodel the Disease-Specific Functions of Orphan Nuclear Receptor TR4.

Testicular receptor 4 (TR4, NR2C2) is an orphan nuclear receptor involved in the regulation of metabolism, inflammation, cardiovascular disease, and cancer. Accumulating evidence indicates that TR4 exhibits functional plasticity, exerting protective or pathogenic effects depending on tissue and disease context, and sometimes displaying opposing roles within the same disease. However, the mechanisms underlying this functional duality remain poorly understood. Recent studies indicate that TR4 activity is determined not only by the receptor itself but also by dynamic coregulatory networks. Through interactions with coactivators, corepressors, epigenetic regulators, and environmental signaling pathways, TR4 integrates metabolic cues to generate context-dependent transcriptional programs. Coactivator networks centered on PGC-1α, steroid receptor coactivator (SRC) family members, and CBP/p300 support oxidative metabolism and anti-inflammatory responses, whereas RIP140-, NCoR/SMRT-, and HDAC-associated networks promote lipid accumulation, chronic inflammation, fibrosis, and tumor progression. Regulators such as JAZF1 further influence TR4 activity by reshaping coregulator recruitment and target-gene selection. In this review, we summarize the structural basis of TR4 regulation and discuss how coregulatory network remodeling governs its functions in metabolic, cardiovascular, inflammatory, and malignant diseases. We propose that TR4 functions as a context-dependent transcriptional platform whose activities are defined by its coregulatory landscape, providing a framework for precision therapies.